The present invention is related to a timing distribution system has been developed for a network-switching product that corrects several non-compliant features from previous systems. The limitations that have been addressed are:                1) Being able to successfully accept a wide range of wandering and jittering inputs that produce the same output when filtered.        2) Having a range of inputs accepted that may actually be outside of the acceptable range for a timing distribution system.        3) Being unable to monitor the frequency of a standby reference signal in order to approve it prior to the failure of a master reference signal.        4) Being unable to monitor the frequency of a standby reference signal in order to provide revertive switching to a previously failed signal.        5) Having no phase discontinuity when switching over to a standby hardware system.        6) Not having any phase discontinuity whatsoever when failing between any like frequency reference.        
This system is believed to be the first of its kind that completely meets all of the industry specifications for timing distribution systems in a network-switching product (Bellcore GR-1244-CORE and GR-253-CORE, Chapter 5, both of which are incorporated by reference herein).